Process for producing organic peroxides

ABSTRACT

A process of the invention allows a cycloalkane to react with oxygen in the presence of a catalytic imide compound having an N-hydroxy (or N-oxo) cyclic imide skeleton and thereby yields a corresponding bis(1-hydroxycycloalkyl)peroxide. The catalytic imide compound includes, for example, a compound represented by following Formula (1):  
                 
 
     wherein R 1  and R 2  are each, for example, a hydrogen atom, a halogen atom, an alkyl group, an aryl group or a cycloalkyl group, where R 1  and R 2  may be combined to form a double bond, an aromatic or non-aromatic ring; and X is an oxygen atom or a hydroxyl group. The cycloalkane includes, for example, a cycloalkane having from 5 to 15 members. The invention can easily produce bis(1-hydroxycycloalkyl)peroxide from an inexpensive material.

TECHNICAL FIELD

[0001] The present invention relates to a process for producingbis(1-hydroxycycloalkyl)peroxides that are useful as, for example, rawmaterials for lactones and lactams.

BACKGROUND ART

[0002] Bis(1-hydroxycycloalkyl)peroxides are useful as, for example, rawmaterials for lactones and lactams. For example, By treatingbis(1-hydroxycyclohexyl)peroxide with an acid, ε-caprolactone, which isimportant as a raw material for a polyester, can be produced in a goodyield (U.S. Pat. No. 4,183,863). By allowing ammonia to act uponbis(1-hydroxycyclohexyl)peroxide, ε-caprolactam, which is useful as araw material for a polyamide, can be obtained (Japanese Examined PatentApplication Publication No. 46-25742).

[0003] Liebig Annalen der Chemie, vol.565, pp. 7 (1949) discloses aprocess for producing a bis(1-hydroxycycloalkyl)peroxide by allowingcyclohexanone to react with hydrogen peroxide. This process, however,requires expensive hydrogen peroxide as a raw material and is notappropriate as an industrial process. PCT International Publication No.WO99/50204 mentions that, by allowing cyclohexanol to react with oxygenin the presence of cyclohexanone and N-hydroxyphthalimide and thenallowing indium chloride to act upon the resulting mixture,bis(1-hydroxycyclohexyl)peroxide is produced in addition toε-caprolactone. This process, however, requires relatively expensivecyclohexanol as a raw material, also requires cyclohexanone and isdisadvantageous.

DISCLOSURE OF INVENTION

[0004] Accordingly, an object of the present invention is to provide aprocess for easily producing a bis(1-hydroxycycloalkyl)peroxide from aninexpensive raw material.

[0005] Another object of the present invention is to provide a processfor directly producing a bis(1-hydroxycycloalkyl)peroxide from acycloalkane and oxygen.

[0006] After intensive investigations to achieve the above objects, thepresent inventors have found that a bis(1-hydroxycycloalkyl)peroxide isdirectly produced from a cycloalkane and oxygen by using a specificcatalyst. The present invention has been accomplished based on thesefindings.

[0007] Specifically, the present invention provides a process forproducing an organic peroxide, the process including the step ofallowing a cycloalkane to react with oxygen in the presence of acatalytic imide compound having an N-hydroxy (or N-oxo) cyclic imideskeleton to yield a corresponding bis(1-hydroxycycloalkyl)peroxide.

[0008] The catalytic imide compound includes, for example, a compoundrepresented by following Formula (1):

[0009] wherein R¹ and R² are the same or different and are each ahydrogen atom, a halogen atom, an alkyl group, an aryl group, acycloalkyl group, a hydroxyl group, an alkoxy group, a carboxyl group,an alkoxycarbonyl group, or an acyl group, where R¹ and R² may becombined to form a double bond, an aromatic or non-aromatic ring; X isan oxygen atom or a hydroxyl group; and one or two of N-substitutedcyclic imido group indicated in the formula may be further formed on theR¹, R², or on the double bond or aromatic or non-aromatic ring formed byR¹ and R². The cycloalkane includes, for example, cycloalkanes eachhaving from 5 to 15 members.

BEST MODE FOR CARRYING OUT THE INVENTION

[0010] [Cycloalkanes]

[0011] Cycloalkanes for use as starting materials in the presentinvention include, but are not limited to, cyclopropane, cyclobutane,cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane,cyclodecane, cyclododecane, cyclotetradecane, cyclohexandecane,cyclooctadecane, cycloicosane, cyclodocosane, cyclotriacontane, andother cycloalkanes each having from about 3 to about 30 members. Amongthem, cyclopentane, cyclohexane, cyclooctane, cyclododecane, and othercycloalkanes each having from about 5 to about 15 members are preferred,of which cyclohexane and cyclododecane are typically preferred.

[0012] These cycloalkanes may have at least one substituent within arange not adversely affecting a reaction. Such substituents include, butare not limited to, halogen atoms, oxo group, hydroxyl group, mercaptogroup, substituted oxy groups (e.g., alkoxy groups, aryloxy groups andacyloxy groups), substituted thio groups, carboxyl group, substitutedoxycarbonyl groups, substituted or unsubstituted carbamoyl groups, cyanogroup, nitro group, substituted or unsubstituted amino groups, alkylgroups (e.g., methyl, ethyl, isopropyl, t-butyl, hexyl, octyl, decyl,and other C₁-C₂₀ alkyl groups, of which C₁-C₄ alkyl groups arepreferred), alkenyl groups, alkynyl groups, cycloalkyl groups,cycloalkenyl groups, aryl groups (e.g., phenyl and naphthyl groups),aralkyl groups (e.g., benzyl group), and heterocyclic groups. Each ofthe cycloalkanes may have an aromatic or non-aromatic carbon ring orheterocyclic ring condensed to the cycloalkane ring within a range notadversely affecting the reaction.

[0013] [Oxygen]

[0014] As oxygen, either of molecular oxygen and nascent oxygen can beused. The molecular oxygen is not specifically limited and includes pureoxygen, oxygen diluted with an inert gas such as nitrogen, helium, argonor carbon dioxide, and air. Oxygen can be formed in the reaction system.The amount of oxygen is generally equal to or more than about 0.5 mole(for example, equal to or more than about 1 mole), preferably from about1 to about 100 moles, and more preferably from about 2 to about 50moles, relative to 1 mole of the substrate cycloalkane. Oxygen is oftenused in excess moles to the substrate.

[0015] [Catalytic Imide Compounds]

[0016] According to the present invention, an imide compound having anN-hydroxy (or N-oxo) cyclic imide skeleton is used as a catalyst. Suchimide compounds include, for example, the compounds represented byFormula (1).

[0017] Of the substituents R¹ and R² in the imide compounds representedby Formula (1), the halogen atom includes iodine, bromine, chlorine andfluorine atoms. The alkyl group includes, but is not limited to, methyl,ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, t-butyl, pentyl,hexyl, heptyl, octyl, decyl, and other straight- or branched-chain alkylgroups each having from about 1 to about 10 carbon atoms. Preferredalkyl groups are alkyl groups each having from about 1 to about 6 carbonatoms, of which lower alkyl groups each having from about 1 to about 4carbon atoms are typically preferred.

[0018] The aryl group includes phenyl and naphthyl groups, for example.Illustrative cycloalkyl groups include cyclopentyl and cyclohexylgroups. Illustrative alkoxy groups are methoxy, ethoxy, propoxy,isopropoxy, butoxy, isobutoxy, t-butoxy, pentyloxy, hexyloxy, and otheralkoxy groups each having from about 1 to about 10 carbon atoms, andpreferably having from about 1 to about 6 carbon atoms. Among them,lower alkoxy groups each having from about 1 to about 4 carbon atoms aretypically preferred.

[0019] Examples of the alkoxycarbonyl group include methoxycarbonyl,ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl,isobutoxycarbonyl, t-butoxycarbonyl, pentyloxycarbonyl,hexyloxycarbonyl, and other alkoxycarbonyl groups each having from about1 to about 10carbon atoms in the alkoxy moiety. Preferred alkoxycarbonylgroups are alkoxycarbonyl groups each having from about 1 to about 6carbon atoms in the alkoxy moiety, of which lower alkoxycarbonyl groupseach having from about 1 to about 4 carbon atoms in the alkoxy moietyare typically preferred.

[0020] The acyl group includes, but is not limited to, formyl, acetyl,propionyl, butyryl, isobutyryl, valeryl, isovaleryl, pivaloyl, and otheracyl groups each having from about 1 to about 6 carbon atoms.

[0021] The substituents R¹ and R² may be identical to or different fromeach other. The substituents R¹ and R² in Formula (1) may be combined toform a double bond, or an aromatic or non-aromatic ring. The preferredaromatic or non-aromatic ring is a 5- to 12-membered ring, andespecially a 6- to 10-membered ring. The ring may be a heterocyclic ringor condensed heterocyclic ring, but it is often a hydrocarbon ring. Suchrings include, but are not limited to, non-aromatic alicyclic rings(e.g., cyclohexane ring and other cycloalkane rings which may have asubstituent, cyclohexene ring and other cycloalkene rings which may havea substituent), non-aromatic bridged rings (e.g., 5-norbornene ring andother bridged hydrocarbon rings which may have a substituent), benzenering, naphthalene ring, and other aromatic rings (including condensedrings) which may have a substituent. The ring is composed of an aromaticring in many cases. The ring may have at least one substituent. Suchsubstituents include, for example, alkyl groups, haloalkyl groups,hydroxyl group, alkoxy groups, carboxyl group, alkoxycarbonyl groups,acyl groups, nitro group, cyano group, amino groups, and halogen atoms.

[0022] In Formula (1), X represents an oxygen atom or a hydroxyl group,and the bond between the nitrogen atom N and X is a single bond or adouble bond.

[0023] On R¹, R², or on the double bond or aromatic or non-aromatic ringformed by R¹ and R², one or two of the N-substituted cyclic imido groupindicated in Formula (1) may be further formed. For example, when R¹ orR² is an alkyl group having two or more carbon atoms, the N-substitutedcyclic imido group may be formed together with the adjacent two carbonatoms constituting the alkyl group. Likewise, when R¹ and R² arecombined to form a double bond, the N-substituted cyclic imido group maybe formed together with the double bond when R¹ and R² are combined toform an aromatic or non-aromatic ring, the N-substituted cyclic imidogroup may be formed with the adjacent two carbon atoms constituting thering.

[0024] Preferred imide compounds include compounds of the followingformulae:

[0025] wherein R³ to R⁶ are the same or different and are each ahydrogen atom, an alkyl group, a haloalkyl group, a hydroxyl group, analkoxy group, a carboxyl group, an alkoxycarbonyl group, an acyl group,a nitro group, a cyano group, an amino group, or a halogen atom, whereadjacent groups of R³ to R⁶ maybe combined to form an aromatic ornon-aromatic ring; A in Formula (1f) is a methylene group or an oxygenatom; and R¹, R² and X have the same meanings as defined above, whereone or two of the N-substituted cyclic imido group indicated in Formula(1c) may be further formed on the benzene ring in Formula (1c).

[0026] In the substituents R³ to R⁶, the alkyl group includes similaralkyl groups to those exemplified above, of which alkyl groups eachhaving from about 1 to about 6 carbon atoms are preferred. The haloalkylgroup includes trifluoromethyl group and other haloalkyl groups eachhaving from about 1 to about 4 carbon atoms. The alkoxy group includessimilar alkoxy groups tot hose mentioned above, of which lower alkoxygroups each having from about 1 to about 4 carbon atoms are preferred.The alkoxycarbonyl group includes similar alkoxycarbonyl groups to thosedescribed above, of which lower alkoxycarbonyl groups each having fromabout 1 to about 4 carbon atoms in the alkoxy moiety are preferred. Theacyl group includes similar acyl groups to those described above, ofwhich acyl groups each having from about 1 to about 6 carbon atoms arepreferred. The illustrative halogen atoms include fluorine, chlorine andbromine atoms. Each of the substituents R³ to R⁶ is often a hydrogenatom, a lower alkyl group having from about 1 to about 4 carbon atoms, acarboxyl group, a nitro group, or a halogen atom. The ring formedtogether by R³ to R⁶ includes similar rings to the aforementioned ringswhich are formed together by R¹ and R². Among them, aromatic ornon-aromatic 5- to 12-membered rings are typically preferred.

[0027] Preferred imide compounds include, for example,

[0028] N-hydroxysuccinimide, N-hydroxymaleimide,

[0029] N-hydroxyhexahydrophthalimide,

[0030] N,N′-dihydroxycyclohexanetetracarboximide,

[0031] N-hydroxyphthalimide, N-hydroxytetrabromophthalimide,

[0032] N-hydroxytetrachlorophthalimide, N-hydroxychlorendimide,

[0033] N-hydroxyhimimide, N-hydroxytrimellitimide,

[0034] N,N′-dihydroxypyromellitimide, and

[0035] N,N′-dihydroxynaphthalenetetracarboximide.

[0036] The imide compounds represented by Formula (1) can be prepared bya conventional imidization process (a process for the formation of animide), such as a process in which a corresponding acid anhydride isallowed to react with hydroxylamine NH₂OH for ring-opening of an acidanhydride group, and the ring is then closed to form an imide.

[0037] Such acid anhydrides include succinic anhydride, maleicanhydride, and other saturated or unsaturated aliphatic dicarboxylicanhydrides, tetrahydrophthalic anhydride, hexahydrophthalic anhydride(1,2-cyclohexanedicarboxylic anhydride),1,2,3,4-cyclohexanetetracarboxylic 1,2-dianhydride, and other saturatedor unsaturated non-aromatic cyclic polycarboxylic anhydrides(alicyclicpolycarboxylic anhydrides), HET anhydride(chlorendic anhydride), himicanhydride, and other bridged cyclic polycarboxylic anhydrides(alicyclicpolycarboxylic anhydrides), phthalic anhydride, tetrabromophthalicanhydride, tetrachlorophthalic anhydride, nitrophthalic anhydride,trimellitic anhydride, methylcyclohexenetricarboxylic anhydride,pyromellitic anhydride, mellitic anhydride,1,8;4,5-naphthalenetetracarboxylic dianhydride, and other aromaticpolycarboxylic anhydrides.

[0038] Typically preferred imide compounds include N-hydroxyimidecompounds derived from alicyclic polycarboxylic anhydrides or aromaticpolycarboxylic anhydrides, of which N-hydroxyphthalimide and otherN-hydroxyimide compounds derived from aromatic polycarboxylic anhydridesare especially preferred.

[0039] Each of the imide compounds having an N-hydroxy (or N-oxo) cyclicimide skeleton can be used alone or in combination. The imide compoundscan be used as being supported by a carrier. As such carriers, activatedcarbon, zeolite, silica, silica-alumina, bentonite, and other porouscarries are often employed. The amount of the imide compound on thecarrier is, for example, from about 0.1 to about 50 parts by weight,preferably from about 0.5 to about 30 parts by weight, and morepreferably from about 1 to about 20 parts by weight, relative to 100parts by weight of the carrier.

[0040] The amount of the imide compound can be selected within a widerange and is, for example, from about 0.000001 to about 1 mole,preferably from about 0.00001 to about 0.5 mole, and more preferablyfrom about 0.0001 to 0.4 mole, relative to 1 mole of the cycloalkane.

[0041] [Promoter (Co-catalyst)]

[0042] According to the invention, a promoter (co-catalyst) can be usedin combination with the catalytic imide compound. Such promotersinclude, for example, metallic compounds. By using the imide compound incombination with the metallic compound, the rate and selectivity of thereaction can be improved.

[0043] Metallic elements constituting the metallic compounds are notspecifically limited and are often metallic elements of the Groups 2 to15 of the Periodic Table of Elements. The term “metallic element” asused herein also includes boron B. Examples of the metallic elementsinclude, of the Periodic Table of Elements, Group 2 elements (e.g., Mg,Ca, Sr and Ba), Groups 3 elements (e.g., Sc, lanthanoid elements andactinoid elements), Group 4 elements (e.g., Ti, Zr and Hf), Group 5elements (e.g., V), Group 6 elements (e.g., Cr, Mo and W), Group 7elements (e.g., Mn), Group 8 elements (e.g., Fe and Ru), Group 9elements (e.g., Co and Rh), Group 10 elements (e.g., Ni, Pd and Pt),Group 11 elements (e.g., Cu), Group 12 elements (e.g., Zn), Groups 13elements (e.g., B, Al and In), Group 14 elements (e.g., Sn and Pb), andGroup 15 elements (e.g., Sb and Bi). Preferred metallic elements includetransition metal elements (elements of Groups 3 to 12 of the PeriodicTable of Elements) and Group 13 elements of the Periodic Table ofElements. Among them, elements of the Groups 5 to 11 and Group 13 of thePeriodic Table of Elements are preferred, of which elements of Groups 5to 9 and Group 13 are typically preferred. Especially, V, Mo, Mn, Co andIn are preferred, of which Mn, Co and In are typically preferred. Thevalency of the metallic element is not specifically limited and is fromabout 0 to about 6 in many cases.

[0044] Such metallic compounds include, but are not limited to,elementary substances, hydroxides, oxides (including complex oxides),halides (fluorides, chlorides, bromides and iodides), salts of oxoacids(e.g., nitrates, sulfates, phosphates, borates, and carbonates), saltsof isopolyacids, salts of heteropolyacids, and other inorganic compoundsof the aforementioned metallic elements; salts of organic acids (e.g.,acetates, propionates, prussiates, naphthenates and stearates),complexes, and other organic compounds of the metallic elements. Ligandsfor constituting the complexes include OH (hydroxo), alkoxy (e.g.,methoxy, ethoxy, propoxy, and butoxy), acyl (e.g., acetyl andpropionyl), alkoxycarbonyl (e.g., methoxycarbonyl and ethoxycarbonyl),acetylacetonato, cyclopentadienyl group, halogenatoms (e.g., chlorineand bromine), CO, CN, oxygen atom, H₂O (aquo), phosphines(triphenylphosphine and other triarylphosphines) and other phosphoruscompounds, NH₃ (ammine), NO, NO₂ (nitro), NO₃ (nitrato),ethylenediamine, diethylenetriamine, pyridine, phenanthroline, and othernitrogen-containing compounds.

[0045] Specific examples of the metallic compounds include, by takingcobalt compounds as an example, cobalt hydroxide, cobalt oxide, cobaltchloride, cobalt bromide, cobalt nitrate, cobalt sulfate, cobaltphosphate, and other inorganic compounds; cobalt acetate, cobaltnaphthenate, cobalt stearate, and other salts of organic acids;acetylacetonatocobalt and other complexes, and other divalent ortrivalent cobalt compounds. Illustrative vanadium compounds include, butare not limited to, vanadium hydroxide, vanadium oxide, vanadiumchloride, vanadyl chloride, vanadium sulfate, vanadyl sulfate, sodiumvanadate, and other inorganic compounds; acetylacetonatovanadium,vanadyl acetylacetonato, and other complexes, and other vanadiumcompounds having a valence of from 2 to 5. Examples of compounds of theother metallic elements include compounds corresponding to theabove-mentioned cobalt or vanadium compounds. Each of these metalliccompounds can be used alone or in combination.

[0046] The amount of the metallic compound is, for example, from about0.001 to about 0.1 mole, and preferably from about 0.005 to about 0.08mole, relative to 1 mole of the imide compound.

[0047] The promoters for use in the present invention also includeorganic salts each comprising a polyatomic cation or a polyatomic anionand its counter ion, which polyatomic cation or anion contains a Group15 or Group 16 element of the Periodic Table of Elements having at leastone organic group combined therewith. By using the organic salts as thepromoters, the rate and selectivity of the reaction can further beimproved.

[0048] In the organic salts, the Group 15 elements of the Periodic Tableof Elements include N, P, As, Sb, and Bi, and the Group 16 elements ofthe Periodic Table of Elements include, for example, O, S, Se and Te.Preferred elements are N, P, As, Sb and S, of which N, P and S aretypically preferred.

[0049] The organic groups to be combined with atoms of the elementsinclude, but are not limited to, hydrocarbon groups which may have asubstituent, and substituted oxy groups. The hydrocarbon groups include,but are not limited to, methyl, ethyl, propyl, isopropyl, butyl,isobutyl, s-butyl, t-butyl, pentyl, hexyl, octyl, decyl, tetradecyl,hexadecyl, octadecyl, allyl, and other straight-or branched-chainaliphatic hydrocarbon groups (alkyl groups, alkenyl groups and alkynylgroups) each having from about 1 to about 30 carbon atoms (preferablyfrom about 1 to about 20 carbon atoms); cyclopentyl, cyclohexyl, andother alicyclic hydrocarbon groups each having from about 3 to about 8carbon atoms; and phenyl, naphthyl, and other aromatic hydrocarbongroups each having from about 6 to about 14 carbon atoms. Substituentswhich the hydrocarbon groups may have include, but are not limited to,halogen atoms, oxo group, hydroxyl group, substituted oxy groups (e.g.,alkoxy groups, aryloxy groups, and acyloxy groups), carboxyl group,substituted oxycarbonyl groups, substituted or unsubstituted carbamoylgroups, cyano group, nitro group, substituted or unsubstituted aminogroups, alkyl groups (e.g., methyl, ethyl, and other C₁-C₄ alkylgroups), cycloalkyl groups, aryl groups (e.g., phenyl and naphthylgroups), and heterocyclic groups. The preferred hydrocarbon groupsinclude, for example, alkyl groups each having from about 1 to about 30carbon atoms, and aromatic hydrocarbon groups (especially, phenyl ornaphthyl group) each having from about 6 to about 14 carbon atoms. Thesubstituted oxy groups include, but are not limited to, alkoxy groups,aryloxy groups and aralkyl oxy groups.

[0050] Examples of the organic salts include organic ammonium salts,organic phosphonium salts, organic sulfonium salts, and other organiconium salts. Such organic ammonium salts include, for example,tetramethylammonium chloride, tetraethylammonium chloride,tetrabutylammonium chloride, tetrahexylammonium chloride,trioctylmethylammonium chloride, triethylphenylammonium chloride,tributyl(hexadecyl)ammonium chloride, di(octadecyl)dimethylammoniumchloride, and other quaternary ammonium chlorides, and correspondingquaternary ammonium bromides, and other quaternary ammonium salts eachhaving four hydrocarbon groups combined with a nitrogen atom;dimethylpiperidinium chloride, hexadecylpyridinium chloride,methylquinolinium chloride, and other cyclic quaternary ammonium salts.Examples of the organic phosphonium salts include tetramethylphosphoniumchloride, tetrabutylphosphonium chloride, tributyl(hexadecyl)phosphoniumchloride, triethylphenylphosphonium chloride, and other quaternaryphosphonium chlorides, and corresponding quaternary phosphoniumbromides, and other quaternary phosphonium salts each having fourhydrocarbon groups combined with a phosphorus atom. Examples of theorganic sulfonium salts include triethylsulfonium iodide,ethyldiphenylsulfonium iodide, and other sulfonium salts each havingthree hydrocarbon groups combined with a sulfur atom.

[0051] The organic salts also include methanesulfonates,ethanesulfonates, octanesulfonates, dodecanesulfonates, and otheralkyl-substituted sulfonates (e.g., C₆-C₁₈ alkyl-substitutedsulfonates); benzenesulfonates, p-toluenesulfonates,naphthalenesulfonates, decylbenzenesulfonates, dodecylbenzenesulfonates,and other aryl-substituted sulfonates which may be substituted with analkyl group (e.g., C₆-C₁₈ alkyl-substituted arylsulfonates); sulfonicacid type ion exchange resins (ion exchangers); and phosphonic acid typeion exchange resins (ion exchangers).

[0052] The amount of the organic salt is, for example, from about 0.001to about 0.1 mole and preferably from about 0.005 to about 0.08 mole,relative to 1 mole of the imide compound.

[0053] According to the process of the present invention, the reactionsystem may include a radical generator or a radical reactionaccelerator. Such components include, but are not limited to, halogens(e.g., chlorine and bromine), per acids (e.g., peracetic acid andm-chloroperbenzoic acid), and peroxides (e.g., hydrogen peroxide,t-butyl hydroperoxide(TBHP), and other hydroperoxides). The system alsoinclude nitric acid, nitrous acid or a salt thereof. The existence ofsuch a component in the system enhances a reaction in some cases. Theamount of the aforementioned component is, for example, from about 0.001to about 0.1 mole relative to 1 mole of the imide compound.

[0054] [Reaction]

[0055] The reaction can be performed in the presence of, or in theabsence of, a solvent. Such solvents include, but are not limited to,benzene and other aromatic hydrocarbons; dichloromethane, chloroform,1,2-dichloroethane, dichlorobenzene, and other halogenated hydrocarbons;t-butanol, t-amyl alcohol, and other alcohols; acetonitrile,benzonitrile, and other nitriles; acetic acid, propionic acid, and otherorganic acids; formamide, acetamide, dimethylformamide (DMF),dimethylacetamide, and other amides; and mixtures of these solvents.

[0056] A reaction temperature can be selected depending on, for example,the type of the reaction material within a range of, for example, fromabout 40° C. to about 200° C., preferably from about 60° C. to about150° C., and more preferably from about 70° C. to about 100° C. Thereaction can be performed at atmospheric pressure or under a pressure(under a load). The reaction can be performed in the presence of, orunder flow of, oxygen in a conventional system such as a batch system,semi-batch system or continuous system.

[0057] According to the present invention, a starting materialcycloalkane represented by Formula (2) yields a correspondingbis(1-hydroxycycloalkyl)peroxide represented by Formula (3) as a resultof a reaction in accordance with the following reaction process chart.For example, cyclohexane yields bis(1-hydroxycyclohexyl)peroxide, andcyclododecane yields bis(1-hydroxycyclododecyl)peroxide.

[0058] In the above formulae, ring Z is a cycloalkane ring.

[0059] After the completion of the reaction, reaction products can beseparated and purified by a technique such as filtration, concentration,distillation, extraction, crystallization, recrystallization,adsorption, column chromatography and other separation means, or anycombination of these separation means. For example, the productbis(1-hydroxycycloalkyl)peroxide can be isolated as a result ofcrystallization by adding a poor solvent such as methanol orcyclohexanone to the reaction mixture.

[0060] The product bis(1-hydroxycycloalkyl)peroxide can be quantitatedby redox titration using, for example, iodometry. It can also bequantitated, for example, by high performance liquid chromatography.

[0061] Industrial Applicability

[0062] The present invention can easily produce abis(1-hydroxycycloalkyl)peroxide from an inexpensive raw material andcan directly produce a bis(1-hydroxycycloalkyl)peroxide from acycloalkane and oxygen.

EXAMPLES

[0063] The present invention will be illustrated in further detail withreference to an example below, which is not intended to limit the scopeof the invention.

Example 1

[0064] In a 100-ml flask, 16.0 g (190 mmol) of cyclohexane, 3.1 g (19mmol) of N-hydroxyphthalimide, 0.048 g (0.19 mmol) of cobalt (II)acetate tetrahydrate and 34.0 g of acetonitrile were placed and wereallowed to react at 90° C. in an atmosphere of oxygen gas at atmosphericpressure for 1 hour with stirring. Reaction products were analyzed tofind that bis(1-hydroxycyclohexyl)peroxide represented by followingFormula (4) was produced in a yield of 20% on the basis of cyclohexane.

1. A process for producing an organic peroxide, the process comprisingthe step of allowing a cycloalkane to react with oxygen in the presenceof a catalytic imide compound having an N-hydroxy (or N-oxo) cyclicimide skeleton to yield a correspondingbis(1-hydroxycycloalkyl)peroxide.
 2. The process for producing anorganic peroxide according to claim 1, wherein the catalytic imidecompound is a compound represented by following Formula (1):

wherein R¹ and R² are the same or different and are each a hydrogenatom, a halogen atom, an alkyl group, an aryl group, a cycloalkyl group,a hydroxyl group, an alkoxy group, a carboxyl group, an alkoxycarbonylgroup, or an acyl group, where R¹ and R² may be combined to form adouble bond or an aromatic or non-aromatic ring; X is an oxygen atom ora hydroxyl group; and one or two of N-substituted cyclic imido groupindicated in the formula may be further formed on the R¹, R², or on thedouble bond or aromatic or non-aromatic ring formed by R¹ and R².
 3. Theprocess for producing an organic peroxide according to claim 1, whereinthe cycloalkane is a cycloalkane having from 5 to 15 members.